It is well known that diverse synthetic resinous materials are, by and large and inherently, mutually incompatible. Essentially because of this, physical admixtures of most given different polymers--such as those gotten from melt blending procedures--are usually opaque blended polymer (i.e., "polyblend") products. The theory and practice of polymer compatibility and blending is nicely documented as a recent presentation set forth in Polymer Blends, Vols. 1 and 2, by D. R. Paul and Seymour Newman, Academic Press (a Subsidiary of Harcourt Brace Jovanovich) Publishers of New York, San Francisco and London (1978).
There are, nonetheless, a fair number of known and established exceptions to the foregoing generality. U.S. Pat. Nos. 3,177,268; 4,083,896; and 4,113,798 and French Pat. No. 1,526,375 are indicative of this. Likewise, the copending, concurrently filed application of the present Applicants pertains, inter alia to impact modification of mass-made ABS (acrylonitrile-butadiene-styrene) and ABS-type resins by means of polyblending thereof with particular grafted acrylate polymers; the same having Ser. No. 255,956; filed Apr. 20, 1981 and entitled "Blends of Grafted Acrylate Polymers and Mass-Made ABS-type Resins".
Notwithstanding, the general incompatibility of polystyrene (i.e., "PS") and most other St (styrene) and the like polymers with PMMA (polymethylmethacrylate) is notoriously well known. The result of attempted mixing of such diverse polymer products is an invariably heterogeneous composition of less than desired properties. Thus, even the mixture of typical styrene/acrylonitrile (i.e., "SAN") copolymers with conventional rubber-modified, high impact polystyrene (i.e., "HIPS") causes reduction of impact strength-values of the involved HIPS. Analogously, due to the recognized incompatibility of the included PS and SAN in the involved matrixes, a markedly brittle blend (usually having less than about a 0.5 ft-lbs/in value in measured Izod Notched Impact strength taken at 73.degree. F. which is 22.8.degree. C.) is had when typical and conventional ABS and HIPS resins are admixed.
Thus, nothing in prior art appears to concern itself realistically with an effective means and composing technique to get well-propertied and remarkably compatibilized polymer blends of acrylate resins with various alkenyl aromatic polymerizates and even other polymer products and to get better and more satisfactory products therewith in the way so indigenously advantageous as in the present contribution to the art.